LONDON/BRUSSELS March 12 (Reuters) - The European Parliament on Wednesday backed a law to curb the use of "super" greenhouse gases used in fridges and air conditioners, which have a global warming potential thousands of times greater than carbon dioxide.

Lawmakers meeting in Strasbourg, France voted 644 to 19 in favour of a European Commission proposal to cut the use of climate-harming hydrofluorocarbons, known as HFCs or 'F-gases', by 79 percent below average 2009-2012 levels by 2030.

"Today marks the beginning of the end for fluorinated gases in Europe," said EU Climate Action Commissioner Connie Hedegaard. "Not only is this good for the climate, but also for the European industries that will invest in more innovative, cleaner alternatives."

Green MEP Bas Eickhout, one of the bill's champions, said "the scaling down of these super greenhouse gases is a significant measure" that reinforces EU leadership on the issue.

Also used in supermarket and industrial refrigeration, HFCs leak from production plants as well as during the operation and disposal of products and equipment that contain them.

They trap up to 23,000 times more heat than carbon dioxide (CO2) and can remain in the atmosphere for thousands of years.

After international action more than two decades ago led to the phasing out of ozone-depleting chlorofluorocarbons (CFCs), HFCs were introduced as industry-supported substitutes.

But European F-gas emissions have risen 60 percent since 1990, leading the Commission to push for the widespread adoption of natural, non-synthetic alternatives such as ammonia or CO2.

EU member states are expected to back the law in an April 14 vote, after which it will enter into force across the 28-nation bloc from 2015.

AMBITIOUS

Green campaigners the Environmental Investigation Agency (EIA) said the bill faced "stiff opposition and alarmist lobbying from vested interests in the chemicals lobby".

Refrigerant gas manufacturer Daikin declined to comment, while Thierry Vanlancker, president of DuPont's chemicals and fluoroproducts arm, said the new rules "reflect the strength of the EU's resolve to address climate change."

He added that DuPont has worked for several years to develop alternative refrigerants that have 99.9 percent lower global warming potential than the gases they were designed to replace.

The European Partnership for Energy and the Environment (EPEE), which represents the EU's heating and cooling industry, welcomed the news.

"This is one of the most ambitious pieces of legislation that the EU has developed in recent years and I am convinced it will help industry move towards alternative solutions in a safe and efficient way," said EPEE director general Andrea Voigt.

Proponents of the bill had pushed for a more sweeping ban, but backed an amended proposal that will see the use of F-gases barred in the servicing and maintenance of old equipment, and curbed in new sectors where viable alternatives are available.

"This decision should act as a catalyst for future negotiations in pursuit of a global deal to address HFCs which, if achieved, could avoid emissions of up to 100 billion tonnes of CO2-equivalent by 2050," said the EIA's Clare Perry.

The United States and China last year agreed to cooperate in drastically reducing the use of HFCs, a goal that was later supported by G20 nations.

But international efforts were hampered after India blocked discussions at annual U.N.-backed talks in Thailand in October.

India has insisted HFC cuts be addressed under the U.N.'s climate change framework and its Kyoto Protocol, and the country opposed proposals to put the issue under the authority of the Montreal Protocol - a widely applauded treaty that from 1989 curbed CFC emissions.

India wants Kyoto's principles - which call for the rich countries that are responsible for the majority of historical greenhouse gas emissions to carry a heavier burden to cut those gases - to apply to HFCs.

Other developing nations, on the other hand, want technical and financial support from the Montreal Protocol's Multilateral Fund to help them cut their F-gas emissions.